1. Field of the Invention
The present invention relates to a distribution automation system for reactive power compensation and its voltage control method, and more particularly, to a distribution automation system and its voltage control method, which can minimize power loss by compensating for the reactive power at each node included in a complex radial distribution system.
2. Discussion of Related Art
A distribution system should be configured to reduce power loss by continuously supplying a voltage of an appropriate magnitude to a user without distortion.
Moreover, a bus voltage supplied to a distribution line varies as the power demand always varies, and thus the magnitude of the bus voltage frequently exceeds an optimal level of a load terminal to which the power demand is connected.
Accordingly, a voltage profile at each load terminal connected to the distribution line should be maintained within an appropriate limit range, and the control settings at such a voltage control device should be properly adjusted to minimize the power and energy loss.
Conventionally, methods for optimizing the voltage and reactive power in power systems have been proposed based on mathematical optimization algorithms such as linear, non-linear, quadratic programming, and Newton and interior methods.
Further, a method based on a fuzzy theory or an expert system method has been employed to control the voltage in the distribution system. In addition, a method for diagnosing a probabilistic load flow based on voltage and reactive power control algorithm has been applied to the method together. And a standardized weighting method which considers the major factors required for the voltage control such as reactive power, feeder loss, voltage drop, voltage profile, etc. has also been proposed.
Meanwhile, with the rapid development of information technology (IT) and communication technology, a distribution automation system, in which these technologies are applied to the distribution system so as to detect a failure by obtaining voltage and current status data at each load terminal of the distribution line even at a remote location, has been developed. Accordingly, a voltage control algorithm for reactive power compensation based on the distribution automation system is required.